1
GATE ME 1989
Subjective
+5
-0
A $$400m$$ long horizontal pipe is to deliver $$900$$ kg of oil
$$\left( {S = 0.9,\,\,\upsilon = 0.0002{m^2}/s} \right)$$ per minute. If the head loss is not to exceed $$8$$ $$m$$ of oil, find the pipe diameter.

(Friction factor in laminar flow: $$f = 64/{R_e}$$)

2
GATE ME 1989
MCQ (Single Correct Answer)
+2
-0.6
The stream function in a two dimensional flow field is given by $$\Psi = {x^2} - {y^2}$$
The magnitude of the velocity at point $$(1,1)$$ is
A
$$2$$
B
$$2\sqrt 2 $$
C
$$4$$
D
$$8$$
3
GATE ME 1989
Subjective
+5
-0
Two black plates, each one meter square, are placed parallel to each other in such a way that the radiation shape factor for the system is $$0.4.$$ If the plates are maintained at $${800^ \circ }C$$ and $${400^ \circ }C$$ respectively, determine the net radiant heat transfer between the plates. Also calculate the net heat exchange if the plates were infinite in size. Stephen Boltzmann constant $$ = 5.67 \times {10^{ - 8}}\,\,W/{m^2}{K^4}$$
4
GATE ME 1989
MCQ (Single Correct Answer)
+1
-0.3
The heat transfer process between a body and its ambient is governed by an internal conductive resistance $$\left( {{\rm I}CR} \right)$$ and an external convective resistance $$(ECR).$$ The body can be considered to be a lumped heat capacity system if
A
$${\rm I}CR > ECR$$
B
$${\rm I}CR$$ is marginally smaller than $$ECR$$
C
$${\rm I}CR = ECR$$
D
$${\rm I}CR$$ is negligible.